May 29, 1999 was a momentous day for the space shuttle Discovery, when it docked with the International Space Station for the first time. Latina Ellen Ochoa was on board and working during the event as mission specialist and engineer. Her responsibilities included coordinating the transfer of nearly two tons of supplies from one vessel to the other, to prepare for the first crew to live on board the space station in 2000. Ochoa assisted two of her fellow astronauts during their lengthy spacewalk, operating the remote robotic arm.